Refrigerant cycle system

ABSTRACT

The degree of freedom when a refrigerant cycle system is constructed in a building or the like is increased. A refrigerant cycle system according to the present disclosure includes a refrigerant cycle, a first power feed unit, a second power feed unit, a first transmission line, and a second transmission line. The power feed unit feeds auxiliary power to a utilization unit of which a power source has been interrupted. The first transmission line connects a heat source unit and the first power feed unit to each other. The second transmission line connects the first power feed unit and the second power feed unit to each other. The second power feed unit is connected to the heat source unit via the first power feed unit.

TECHNICAL FIELD

The present disclosure relates to a refrigerant cycle system.

BACKGROUND ART

Conventionally, there is a refrigerant cycle including a plurality of indoor units and a plurality of power feed units for one outdoor unit. As indicated in NPL 1 (“Mitsubishi Electric Building-air-conditioning Multi-air-conditioner System Design and Construction Manual”, Mitsubishi Electric Corporation, issued in July, 2013, p. 146, see the drawing), an outdoor unit, indoor units, and power feed units are connected in parallel via communication lines.

SUMMARY OF INVENTION Technical Problem

The degree of freedom when a refrigerant cycle system is constructed in a building or the like is increased.

Solution to Problem

A refrigerant cycle system according to a first aspect includes a refrigerant cycle, a first power feed unit, a second power feed unit, a first transmission line, and a second transmission line. The refrigerant cycle includes a heat source unit, a first utilization unit group, and a second utilization unit group. When a power source of each utilization unit of the first utilization unit group has been interrupted, the first power feed unit feeds auxiliary power to the utilization unit of which the power source has been interrupted. The first power feed unit is a unit that differs from the heat source unit. When a power source of each utilization unit of the second utilization unit group has been interrupted, the second power feed unit feeds auxiliary power to the utilization unit of which the power source has been interrupted. The second power feed unit is a unit that differs from the heat source unit. The first transmission line connects the heat source unit and the first power feed unit to each other. The second transmission line connects the first power feed unit and the second power feed unit to each other. The second power feed unit is connected to the heat source unit via the first power feed unit.

Thus, the degree of freedom when the refrigerant cycle system is constructed in a building or the like is increased.

A refrigerant cycle system according to a second aspect is the system according to the first aspect in which the heat source unit, the first power feed unit, and the second power feed unit are connected in series by the first transmission line and the second transmission line.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic diagram illustrating a configuration of a refrigerant cycle system.

FIG. 2 is a schematic diagram illustrating the configuration of the refrigerant cycle system.

FIG. 3 is a flowchart presenting a flow of processing of the refrigerant cycle system.

DESCRIPTION OF EMBODIMENTS

A refrigerant cycle system 1 according to an embodiment of the present disclosure is described below. The embodiment described below is a specific example, and it is not intended that the embodiment limits the technical scope, and the embodiment may be properly modified in a range not departing from the gist.

(1) General Configuration

FIG. 1 is a schematic diagram illustrating an example of a configuration of the refrigerant cycle system 1 according to the present embodiment. The refrigerant cycle system 1 illustrated in FIG. 1 mainly includes an outdoor unit 10, a first indoor unit group 20A including a plurality of indoor units, a second indoor unit group 20B including a plurality of indoor units, a first power feed unit 30 a, a second power feed unit 30 b, and a transmission line 40. The first indoor unit group 20A includes three indoor units 20 a, 20 b, and 20 c. The second indoor unit group 20B includes three indoor units 20 d, 20 e, and 20 f.

The outdoor unit 10 and the respective indoor units 20 a, 20 b, 20 c, 20 d, 20 e, and 20 f included in the refrigerant cycle system 1 are connected to one another by a refrigerant pipe 2 (see FIG. 2) to constitute a refrigerant cycle. The outdoor unit 10, the respective indoor units 20 a, 20 b, 20 c, 20 d, 20 e, and 20 f, the first power feed unit 30 a, and the second power feed unit 30 b included in the refrigerant cycle system 1 are connected to one another by the transmission line 40. Thus, the respective units can communicate with one another.

The number of indoor units connectable to one outdoor unit is determined depending on the capacity, performance, and the like of the outdoor unit. The number of indoor units connectable to the outdoor unit 10 according to the present embodiment is, for example, 16; however, the number is not limited thereto. The arrangement of the power feed units is not limited to the arrangement illustrated in FIG. 1. The number of power feed units is not limited to the number in the arrangement. According to the present disclosure, it is sufficient that the refrigerant cycle system 1 includes at least one outdoor unit, one or more indoor unit groups each including one or more indoor units, and one or more power feed units.

The refrigerant pipe 2 is branched using a branch pipe and connects the outdoor unit 10 and the respective indoor units 20 a, 20 b, 20 c, 20 d, 20 e, and 20 f to one another. Refrigerant flows in the refrigerant pipe 2. In this case, the type of refrigerant is not limited.

(2) Specific Configuration of Refrigerant Cycle System 1

The outdoor unit 10, the indoor unit 20 a, and the first power feed unit 30 a included in the refrigerant cycle system 1 are described below with reference to FIG. 2. In this case, the refrigerant cycle system illustrated in FIG. 2 is part illustrated in an enlarged manner (part surrounded by a broken line) of the refrigerant cycle system 1 illustrated in FIG. 1 for the convenience of description. Description is given according to the present embodiment based on an assumption that the respective indoor units 20 b, 20 c, 20 d, 20 e, and 20 f included in the refrigerant cycle system 1 have configurations similar to that of the indoor unit 20 a illustrated in FIG. 2, and the second power feed unit 30 b included in the refrigerant cycle system 1 has a configuration similar to that of the first power feed unit 30 a illustrated in FIG. 2. Each configuration is a specific example and of course may be properly modified within a scope not departing from the gist, and each unit of course may differ from the other units.

(2-1) Outdoor Unit 10

As illustrated in FIG. 2, the outdoor unit 10 serving as a heat source unit is connected to a power source 11 that is a commercial power source and that serves as a main power source of the outdoor unit 10. The outdoor unit 10 includes an outdoor heat exchanger 12, an outdoor fan 13, a compressor 14, an outdoor control unit 15, and a communication unit 16. The outdoor heat exchanger 12 condenses or evaporates refrigerant flowing through the refrigerant pipe 2 to perform heat exchange. The outdoor fan 13 sends air to the outdoor heat exchanger 12 to cause the refrigerant to exchange heat with air. The compressor 14 compresses and circulates the refrigerant in the refrigerant pipe 2. The outdoor control unit 15 controls the entire outdoor unit 10 and refrigerant cycle system 1. The communication unit 16 communicates with the other units.

The respective configurations included in the outdoor unit 10 function when power is fed from the power source 11 through a power source line.

(2-2) Indoor Unit 20 a

The indoor unit 20 a serving as a utilization unit is connected to a power source 21 a that is a commercial power source and that serves as a main power source of the indoor unit 20 a. The indoor unit 20 a includes an indoor heat exchanger 22 a, an indoor fan 23 a, an expansion valve 24 a, an indoor control unit 25 a, a communication unit 26 a, and an interruption detection unit 27 a. The indoor heat exchanger 22 a condenses or evaporates refrigerant flowing through the refrigerant pipe 2 to perform heat exchange. The indoor fan 23 a sends air to the indoor heat exchanger 22 a to cause the refrigerant to exchange heat with air. The expansion valve 24 a adjusts the amount of refrigerant flowing through the refrigerant pipe 2. The indoor control unit 25 a controls the entire indoor unit 20 a. The communication unit 26 a communicates with the other units. When detecting that the feed of power from the power source 21 a has been interrupted, the interruption detection unit 27 a transmits an interruption signal to the outdoor control unit 15 of the outdoor unit 10. The interruption signal includes a signal for notifying that the main power source has been interrupted, and identification information on the indoor unit of which the main power source has been interrupted. The identification information on the indoor unit is information unique to each indoor unit. The identification information on each of the indoor units is stored in the outdoor control unit 15 of the outdoor unit 10.

In a case where the feed of power from the power source 21 a has not been interrupted, the respective configurations included in the indoor unit 20 a function when power is fed from the power source 21 a through a power source line.

(2-3) First Power Feed Unit 30 a

The first power feed unit 30 a is connected to a power source 31 a that is a commercial power source and that serves as a main power source of the first power feed unit 30 a. The first power feed unit 30 a includes a power feed control unit 32 a that controls the entire power feed unit 30 a, and a communication unit 33 a that communicates with the other units.

The respective configurations included in the first power feed unit 30 a function when power is fed from the power source 31 a through a power source line.

The number of indoor units to which a power feed unit can simultaneously feed power is determined in advance depending on the performance and the like of the power feed unit. Note that power that is fed from the power feed unit to an indoor unit is used as auxiliary power.

The auxiliary power is mainly used to adjust the opening degree of the expansion valve of the indoor unit. In addition, the auxiliary power may be used for various actuator operations in the indoor unit. Examples of the actuator operations include an operation of closing a grill panel included in the indoor unit, and an operation of collecting various pieces of information relating to the indoor unit. The actuator operations that are performed using the auxiliary power are operations set in advance.

The power feed unit that feeds the auxiliary power to each indoor unit is set in advance. When the feed of power of the main power source to each indoor unit has been interrupted, the set power feed unit feeds auxiliary power.

For example, in FIG. 1, the first power feed unit 30 a feeds auxiliary power to the indoor units 20 a, 20 b, and 20 c. The second power feed unit 30 b feeds auxiliary power to the indoor units 20 d, 20 e, and 20 f Processing of a power feed unit to feed auxiliary power to an indoor unit will be described in detail later.

(2-4) Transmission Line 40

As illustrated in FIG. 1, the transmission line 40 connects the respective units included in the refrigerant cycle system 1.

The transmission line 40 is normally used mainly for communication and enables communication among the respective communication units. In addition, the transmission line 40 has a role as a power source line for feeding auxiliary power from a power feed unit to an indoor unit in a case where the main power source of the indoor unit has been interrupted. In other words, the transmission line 40 is used for both transmission and power feed.

In the present embodiment, as illustrated in FIG. 1, the transmission line 40 includes a first transmission line 41, a second transmission line 42, and a third transmission line 43.

The first transmission line 41 connects in series the outdoor unit 10 and the first power feed unit 30 a.

The second transmission line 42 connects in series the first power feed unit 30 a and the second power feed unit 30 b. Specifically, the second transmission line 42 includes transmission lines 42 a, 42 b, 42 c, and 42 d that connect the respective units, and connect the first power feed unit 30 a, the respective indoor units 20 a, 20 b, and 20 c included in the first indoor unit group 20A, and the second power feed unit 30 b. In this case, it is sufficient that the second transmission line 42 connects in series the first power feed unit 30 a and the second power feed unit 30 b, and the connection form of the respective indoor units 20 a, 20 b, and 20 c included in the first indoor unit group 20A is not limited. The indoor units 20 a, 20 b, and 20 c are connected, for example, in sequential order.

The third transmission line 43 connects in series the second power feed unit 30 b and a third power feed unit (not illustrated). Specifically, the third transmission line 43 includes transmission lines 43 a, 43 b, 43 c, and 43 d that connect the respective units, and connects the second power feed unit 30 b, the respective indoor units 20 d, 20 e, and 20 f included in the second indoor unit group 20B, and the third power feed unit. In this case, it is sufficient that the third transmission line 43 connects in series the second power feed unit 30 b and the third power feed unit, and the connection form of the respective indoor units 20 d, 20 e, and 20 f included in the second indoor unit group 20B is not limited.

(3) Processing of Refrigerant Cycle System 1

FIG. 3 is a flowchart illustrating an example of processing of the refrigerant cycle system 1 according to the embodiment of the present disclosure. The flowchart presents a case where the main power source to the indoor unit 20 a included in the refrigerant cycle system 1 illustrated in FIG. 1 is interrupted and auxiliary power is fed to the indoor unit 20 a from the first power feed unit 30 a included in the refrigerant cycle system 1 through the transmission line 40.

First, in step S1, the indoor unit 20 a starts various types of processing in a state fed with power from the power source 21 a. The indoor unit 20 a in this state causes the respective configurations to function and can perform an air conditioning operation such as cooling or heating.

In step S2, the interruption detection unit 27 a of the indoor unit 20 a determines whether or not the feed of power from the power source 21 a has been interrupted. In step S2, when the interruption detection unit 27 a does not detect an interruption of power from the power source 21 a (S2: NO), the indoor unit 20 a continues the air conditioning operation and the interruption detection unit 27 a continues the determination.

In contrast, in step S2, when the interruption detection unit 27 a detects an interruption of power from the power source 21 a (S2: YES), the indoor unit 20 a switches the feed source of power for the indoor unit 20 a from the power source 21 a to the first power feed unit 30 a (step S3). In other words, the indoor unit 20 a starts feed of auxiliary power from the first power feed unit 30 a through the transmission line 40.

In step S4, the indoor unit 20 a outputs the interruption signal to the outdoor unit 10 through the transmission line 40.

In step S5, the outdoor control unit 15 of the outdoor unit 10 transmits an opening degree adjustment instruction of the expansion valve 24 a to the indoor unit 20 a. The opening degree adjustment instruction is an instruction for completely opening the expansion valve 24 a, for completely closing the expansion valve 24 a, for increasing the opening degree, or for decreasing the opening degree. Accordingly, an oil return operation of the indoor unit 20 a or the like can be performed. The outdoor control unit 15 of the outdoor unit 10 may transmit operation instructions for instructing various actuator operations to the indoor unit 20 a. The indoor control unit 25 a of the indoor unit 20 a controls the various types of actuators based on the operation instructions.

In step S6, the indoor control unit 25 a of the indoor unit 20 a adjusts the opening degree of the expansion valve 24 a based on the opening degree adjustment instruction from the outdoor unit 10.

In step S7, the interruption detection unit 27 a of the indoor unit 20 a determines whether or not the power from the power source 21 a has been interrupted. In other words, it is determined whether or not power feed from the main power source has been recovered. In step S7, when the interruption detection unit 27 a detects an interruption of power from the power source 21 a (S7: YES), the interruption detection unit 27 a repeats the determination and continues the power feed from the first power feed unit 30 a.

In contrast, in step S7, when the interruption detection unit 27 a does not detect an interruption of power from the power source 21 a (S7: NO), in other words, when the power feed from the main power source has been resumed, the power feed source of the indoor unit 20 a is switched from the first power feed unit 30 a to the power source 21 a (step S8).

With the above-described processing, the processing of the feed of the auxiliary power to the indoor unit 20 a from the first power feed unit 30 a through the transmission line 40 in the case where the main power source of the indoor unit 20 a has been interrupted is ended.

(4) Features

The refrigerant cycle system 1 according to the present embodiment includes the refrigerant cycle, the first power feed unit 30 a, the second power feed unit 30 b, the first transmission line 41, and the second transmission line 42. The refrigerant cycle includes the outdoor unit 10 serving as the heat source unit, the first indoor unit group 20A serving as a first utilization unit group, and the second indoor unit group 20B serving as a second utilization unit group. When the power source of each of the indoor units 20 a, 20 b, and 20 c of the first indoor unit group 20A has been interrupted, the first power feed unit 30 a feeds auxiliary power to the utilization unit of which the power source has been interrupted. The first power feed unit 30 a is a unit that differs from the outdoor unit 10. When the power source of each of the utilization units 20 d, 20 e, and 20 f of the second indoor unit group 20B has been interrupted, the second power feed unit 30 b feeds auxiliary power to the utilization unit of which the power source has been interrupted. The second power feed unit 30 b is a unit that differs from the outdoor unit 10. The first transmission line 41 connects the outdoor unit 10 and the first power feed unit 30 a to each other. The second transmission line 42 connects the first power feed unit 30 a and the second power feed unit 30 b to each other. The second power feed unit 30 b is connected to the outdoor unit 10 via the first power feed unit 30 a.

Moreover, in the refrigerant cycle system 1 according to the present embodiment, the outdoor unit 10, the first power feed unit 30 a, and the second power feed unit 30 b are connected in series by the first transmission line 41 and the second transmission line 42.

When the outdoor unit and the power feed unit can be connected only in parallel, the length of the transmission line that connects the outdoor unit and the power feed unit to each other may be too long. In such a case, the construction of wiring takes time and effort, leading to an increase in the cost for the construction.

In the refrigerant cycle system 1 according to the present embodiment, the outdoor unit 10, the first power feed unit 30 a, and the second power feed unit 30 b are connected in series by the first transmission line 41 and the second transmission line 42. Hence, the construction of wiring among the respective units can be efficiently performed.

Thus, the outdoor unit and the power feed unit can be disposed at locations farther than those of related art. Accordingly, the degree of freedom when the refrigerant cycle system is constructed in a building or the like is increased.

(5)

The embodiment of the present disclosure has been described above, and it is understood that the embodiment and details can be modified in various ways without departing from the gist and scope of the present disclosure described in the claims.

REFERENCE SIGNS LIST

-   -   1 refrigerant cycle system     -   10 heat source unit     -   20A first utilization unit group     -   20B second utilization unit group     -   20 a, 20 b, 20 c, 20 d, 20 e, 20 f utilization unit     -   21 a, 21 b, 21 c, 21 d, 21 e, 21 f power source     -   30 a first power feed unit     -   30 b second power feed unit     -   41 first transmission line     -   42 second transmission line

CITATION LIST Non Patent Literature

-   NPL 1: “Mitsubishi Electric Building-air-conditioning     Multi-air-conditioner System Design and Construction Manual”,     Mitsubishi Electric Corporation, issued in July, 2013, p. 

1. A refrigerant cycle system comprising: a refrigerant cycle including a heat source unit, a first utilization unit group, and a second utilization unit group; a first power feed unit that differs from the heat source unit and, when a power source of each utilization unit of the first utilization unit group has been interrupted, feeds auxiliary power to the utilization unit of which the power source has been interrupted; a second power feed unit that differs from the heat source unit and, when a power source of each utilization unit of the second utilization unit group has been interrupted, feeds auxiliary power to the utilization unit of which the power source has been interrupted; a first transmission line that connects the heat source unit and the first power feed unit to each other; and a second transmission line that connects the first power feed unit and the second power feed unit to each other, wherein the second power feed unit is connected to the heat source unit via the first power feed unit.
 2. The refrigerant cycle system according to claim 1, wherein the heat source unit, the first power feed unit, and the second power feed unit are connected in series by the first transmission line and the second transmission line. 